Cisco Cisco Agent Desktop 8.5 Referências técnicas
VoIP Monitoring Assumptions
18
of
34
November 26, 2003
5.0 VoIP Monitoring Assumptions
5.1 Server Monitoring
5.1.1
VoIP Traffic Exposure
In order for monitoring and recording to function correctly, the VoIP Monitor
service must be exposed to the IP traffic containing the RTP packets to be
sniffed. This means the voice traffic must be presented to the VoIP Monitor ser-
vice service’s network interface. This is done by setting up SPAN or RSPAN on
the switches to which the agent phones are connected.
service must be exposed to the IP traffic containing the RTP packets to be
sniffed. This means the voice traffic must be presented to the VoIP Monitor ser-
vice service’s network interface. This is done by setting up SPAN or RSPAN on
the switches to which the agent phones are connected.
SPAN and RSPAN configurations specify one or more ports or VLANs on a
switch as source ports and a single port as a destination port. The destination
port is the port used by the machine running the VoIP Monitor service to con-
nect to the switch.
switch as source ports and a single port as a destination port. The destination
port is the port used by the machine running the VoIP Monitor service to con-
nect to the switch.
The IP traffic coming over the source ports is copied and sent to the destination
port. The VoIP Monitor service examines each packet to see if it should be cop-
ied and sent to a supervisor for monitoring, or to the Recording & Statistics ser-
vice for recording.
port. The VoIP Monitor service examines each packet to see if it should be cop-
ied and sent to a supervisor for monitoring, or to the Recording & Statistics ser-
vice for recording.
Ideally, the VoIP Monitor service only needs to sniff the packets that it is inter-
ested in (voice packets). If voice VLANs are not used, or the switch only sup-
ports port sniffing (see Section B.5 on page 26), then it is sniffing the IP phone
port directly, and more extraneous network traffic is processed by the VoIP
Monitor service. This decreases the capacity of the service.
ested in (voice packets). If voice VLANs are not used, or the switch only sup-
ports port sniffing (see Section B.5 on page 26), then it is sniffing the IP phone
port directly, and more extraneous network traffic is processed by the VoIP
Monitor service. This decreases the capacity of the service.
5.1.2
Layer 2 Switching Domains
VoIP traffic is sniffed and copied using the designated IP phone MAC address.
As a result, there can be no layer 3 routing performed on the VoIP packets
because that changes the MAC address of the Ethernet frames.
As a result, there can be no layer 3 routing performed on the VoIP packets
because that changes the MAC address of the Ethernet frames.
There can be no routers between the agent IP phones that are being moni-
tored/recorded and the ports being sniffed (exposed via SPAN and RSPAN).
tored/recorded and the ports being sniffed (exposed via SPAN and RSPAN).
5.1.3
Single Copy of VoIP Packets
When configuring SPAN and RSPAN on the switch(es), it is important to verify
that only a single copy of a VoIP packet is sent to the VoIP Monitor service.
that only a single copy of a VoIP packet is sent to the VoIP Monitor service.
If SPAN is set up to monitor two agent ports, and those agents are on a call
with each other, the voice packets exchanged between the two IP phones can
be sent to the VoIP Monitor service twice—once when it leaves Agent A’s
phone, and again when it is received by Agent B’s phone.
with each other, the voice packets exchanged between the two IP phones can
be sent to the VoIP Monitor service twice—once when it leaves Agent A’s
phone, and again when it is received by Agent B’s phone.